When people complain about prejudice against fat people, this is what they mean.

I fail to understand why someone's size would make their advice less credible, particularly on topics other than weight loss. If anything, being at higher risk would dispose them to take the virus more seriously.

After all, "trying to eat healthy" is rarely successful. The vast majority of dieters do not succeed in achieving long-term weight loss.

So if it works for a person with a lot of bad habits you think it's a bad idea? Wouldn't something that works for a person with a lot of bad habits be even better?

Hypocrisy speaks less to the quality of someone's advice than it does to their willpower.